Over on the electrical forum there's a topic about the 455 kHz frequency used in TMCC. I posted info about the MC3372 integrated circuit used on the R2LC which contains an oscillator, mixer, IF amp, discriminator, filter, squelch etc, etc. It also has a signal strength output that can hook up directly to a meter. Has anybody pursued this to see how it works? I just dug up a proper meter out of my junk box and may look into this.
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You'll be the first, let us know what you find out. Maybe we could come up with a little signal strength car to drag around the layout. 
My thoughts exactly. Just need some lousy weather to drive me downstairs and work on it.
There are FCC regulations for "non Licensed" devices. It used to be 100milli watts. (.100 watts)Don
Don, we're not talking about broadcasting here, just measuring what is available on the rails.
I thought the command base signal "antenna"(455kc) is between the outer rail and the ground wiring in the house and the loco picks this up on it's antenna? Don
Finally got to try it and it works great. I only have a 50ua meter and it pegs with any antenna. Without an antenna I get about 30ua. The data sheet says the signal strength output ranges 0-60ua and to use a 0-100ua meter. I'll figure out what size resistor to put on the meter to knock it back half. Then I'll be looking for a car that has a center rail pickup and mount the meter on it for a test run around my layout. The other use I envision is when installing TMCC boards into a conventional engine I can now measure how effective the antenna is.
Get a reading and try some parallel resistors until you cut it by half, that will be.
Just found out that the newer TMCC receiver board the R4LC also uses the same Motorola IF chip and therefore has the signal strength output.
So, let's see the signal strength test car!
I'm looking forward to seeing his finished car too (especially a video of it in use.)
I may consider adding that capability to my voltage test car, then it would be an all-in-one unit.
If this did DCS signal strength, I'd probably work on it, but I don't have any TMCC issues. 
Gary E. You mentioned an "electrical forum". How do I get to it?
Thx, GRJ
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